'Stroke surge' seen in middle-aged US women

NEW YORK (Reuters Health) - Women between 45 and 54 years old are more than twice as likely as their male counterparts to suffer a stroke, a new study shows.

"Prompt and close attention may need to be paid to the cardiovascular health of women in their mid-30s to mid-50s with a goal of mitigating this burden," Dr. Amytis Towfighi of the University of California, Los Angeles and colleagues conclude.

Stroke most commonly occurs in people 65 and older, the researchers note, but younger women can have risk factors for stroke such as pregnancy, hormone replacement use, and frequent migraine that aren't seen in older women or men.

To investigate stroke prevalence in midlife and identify risk factors for both sexes, the researchers looked at 17,061 US men and women aged 35 to 64 who participated in the National Health and Nutrition Examination Survey between 1999 and 2004.

Women aged 45 to 54 years were 2.39 times as likely as men of the same age to have a stroke, the researchers found. Having heart disease increased a woman's stroke risk nearly 13-fold, while women with the largest waist circumference were at 1.5-fold greater risk than those with the smallest waists.

The data also showed that going from the 35- to 44-year-old age group to the 45- to 54-year-old group increased a woman's likelihood of having a stroke more than 4-fold.

Blood pressure and cholesterol rose more quickly with age among women than among men, which could help explain the gender difference, Towfighi and colleagues note. Past or current use of hormone replacement therapy had no effect on stroke risk.

While the current study, which covers a six-year period, is too short to provide definitive information on any trends in stroke risk based on gender, the researchers say, other research has shown increases in the likelihood of stroke as women reach midlife.

Women "seem generally ill informed" about their heart disease risk factors, the researchers add, while doctors may often underestimate a woman's risk.

"Our study suggests a substantial toll of stroke among women aged 45 to 54 years that may be amenable to optimal control of modifiable vascular risk factor," they conclude.

SOURCE: Neurology, November 13, 2007.